This invention relates to novel compounds that are useful as post-emergent herbicides, particularly against broadleaf weeds. The compounds are derivatives of N-phosphonomethylglycine which is itself an efficient non-selective post-emergent herbicide as is fully described in U.S. Pat. No. 3,799,758.
The systemic herbicidal activity of a compound is often not readily predictable, largely because the precise mode of operation of systemic herbicides is not fully understood. It is, therefore, difficult to predict which combination of functional groups will be effective.
A small group of compounds has now been identified which, unlike a number of closely related compounds, displays post-emergent herbicidal activity especially against broadleaf weeds.